1. Field of the Invention
The invention relates to a device that scans in a raster mode, particularly a raster microscope, with compensation of the disturbing effects of mechanical vibrations on the scanning process.
Devices which scan a specimen in a raster scanning process have achieved great importance in recent years, particularly in the high resolution investigation of specimens, and above all because of improved displacement devices, for example, highly accurate piezo translators, and the advancing development in the production of sensors and sensing elements which, according to the form of embodiment, receive a tunnel current or indicate the action of a force. The topography of a specimen can easily be surveyed, or locally resolved bonding conditions, for example of macromolecules, can be disclosed. Here resolutions down to the nanometer or subnanometer range are attained. For this reason, the actual resolving ability of such devices depends strongly on the external effects from the surroundings. A large role is played here by mechanical vibrations, for example, air vibrations or also bodily vibrations, which can be produced by movements of the building, for example. The disturbing motions produced in this manner, for example those of the microscope table on which the specimen is supported, can easily be of the order of several micrometers, which corresponds to a signal to noise ratio of &lt;10.sup.-3. The high resolution of the devices can thus be only used when the disturbing effect is reduced by corresponding devices.
2. Discussion of Relevant Art
According to the state of the art, active or passive vibration damping or vibration insulating devices are used, for example. However, such devices are very expensive. Particularly at very low disturbing frequencies, such as can arise, for example, from vibrations of buildings, these devices moreover offer only a limited protection. In addition, such systems are extremely slow, because of their intrinsic vibration behavior.